X-Git-Url: http://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Ftcon%2F_info;h=50dc0a5cbe785927feb833a3382007b0a21478e6;hp=67923a0aecf61f497d38857bc492bb67eb7cde6a;hb=88ed9bfe13c4bd2c72b0a2513cecf9ec0f19b792;hpb=5c451bbbed80e3bcb1f6be4301026ece01ab1309

diff --git a/ccan/tcon/_info b/ccan/tcon/_info
index 67923a0a..50dc0a5c 100644
--- a/ccan/tcon/_info
+++ b/ccan/tcon/_info
@@ -1,4 +1,5 @@
 #include "config.h"
+#include <stdio.h>
 #include <string.h>
 
 /**
@@ -8,7 +9,55 @@
  * is then a set of macros which check the type canary before calling
  * the generic routines.
  *
- * License: Public domain
+ * Example:
+ *	#include <ccan/tcon/tcon.h>
+ *	#include <stdio.h>
+ *
+ *	// A simple container class.  Can only contain one thing though!
+ *	struct container {
+ *		void *contents;
+ *	};
+ *	static inline void container_add_raw(struct container *c, void *p)
+ *	{
+ *		c->contents = p;
+ *	}
+ *	static inline void *container_get_raw(struct container *c)
+ *	{
+ *		return c->contents;
+ *	}
+ *
+ *	// This lets the user define their container type; includes a
+ *	// "type canary" to check types against.
+ *	#define DEFINE_TYPED_CONTAINER_STRUCT(name, type) \
+ *		struct name { struct container raw; TCON(type canary); }
+ *
+ *	// These macros make sure the container type and pointer match.
+ *	#define container_add(c, p) \
+ *		container_add_raw(&tcon_check((c), canary, (p))->raw, (p))
+ *	#define container_get(c) \
+ *		tcon_cast((c), canary, container_get_raw(&(c)->raw))
+ *
+ *	// Now, let's define two different containers.
+ *	DEFINE_TYPED_CONTAINER_STRUCT(int_container, int *);
+ *	DEFINE_TYPED_CONTAINER_STRUCT(string_container, char *);
+ *
+ *	int main(int argc, char *argv[])
+ *	{
+ *		struct int_container ic;
+ *		struct string_container sc;
+ *
+ *		// We would get a warning if we used the wrong types...
+ *		container_add(&ic, &argc);
+ *		container_add(&sc, argv[argc-1]);
+ *
+ *		printf("Last arg is %s of %i arguments\n",
+ *		       container_get(&sc), *container_get(&ic) - 1);
+ *		return 0;
+ *	}
+ *	// Given "foo" outputs "Last arg is foo of 1 arguments\n"
+ *	// Given "foo bar" outputs "Last arg is bar of 2 arguments\n"
+ *
+ * License: CC0 (Public domain)
  *
  * Author: Rusty Russell <rusty@rustcorp.com.au>
  */
@@ -22,5 +71,10 @@ int main(int argc, char *argv[])
 		return 0;
 	}
 
+	if (strcmp(argv[1], "testdepends") == 0) {
+		printf("ccan/build_assert\n");
+		return 0;
+	}
+
 	return 1;
 }